1. Technical Field
The present invention relates to a switching circuit and a test apparatus.
2. Related Art
A switch is used in a test apparatus of a semiconductor circuit, for example. A plurality of resistors for measuring current may be provided between a device under test and the driver of the test apparatus, and the switch may be used to switch which of the current measurement resistors is connected, as shown in Japanese Patent Application Publication No. 2008-51641, for example. In this way, the current measurement range can be switched.
A reed relay can be used as the switch described above. However, a reed relay has portions that are mechanically driven, which results in a short lifespan. Furthermore, a semiconductor switch such as a photocoupler can be used as the switch described above. However, the insulation withstand voltage of a semiconductor switch is more difficult to increase than the insulation withstand voltage of the reed relay. Therefore, using a semiconductor switch in a line transmitting high voltage is difficult.